Wherever the production of harmful greenhouse gases cannot be prevented, they should be converted into something useful: this approach is called "carbon capture and utilisation".
Wherever the production of harmful greenhouse gases cannot be prevented, they should be converted into something useful: this approach is called "carbon capture and utilisation". Special catalysts are needed for this. Until now, however, the problem has been that a layer of carbon quickly forms on these catalysts - this is called "coking" - and the catalyst loses its effect. At TU Wien, a new approach was taken: tiny metallic nanoparticles were produced on perovskite crystals through special pre-treatment. The interaction between the crystal surface and the nanoparticles then ensures that the desired chemical reaction takes place without the dreaded coking effect.
Dry reforming: Greenhouse gases become synthesis gas
Carbon dioxide (CO2) and methane are the two human-made greenhouse gases that contribute most to climate change. Both gases often occur in combination, for example in biogas plants. "So-called methane dry reforming is a method that can be used to convert both gases into useful synthesis gas at the same time," says Prof. Christoph Rameshan from the Institute of Materials Chemistry at TU Wien. "Methane and carbon dioxide are turned into hydrogen and carbon monoxide - and it is then relatively easy to produce other hydrocarbons from them, right up to biofuels."
The big problem here is the stability of the catalysts: "The metal catalysts that have been used for this process so far tend to produce tiny carbon nanotubes," explains Florian Schrenk, who is currently working on his dissertation in Rameshan's team. These nanotubes deposit as a black film on the surface of the catalyst and block it.
Read more at: Vienna University of Technology
Florian Schrenk (left) and Christoph Rameshan (Photo Credit: TU Wien)